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Discussion Starter · #1 ·
With 15,335 miles on my Volt since December 28th, it's time to take old #95 on another road trip! When we first got the car we headed on a 3,500ish mile road trip from San Diego to Texas and back. Needless to say, my lifetime MPG average isn't stellar. It hasn't helped that after going through 4 EVSEs the car's had a month or so of running as a pure gasser. Adding to that a trip to the Bay Area, and many trips to LA and around the local mountains...

So starting tomorrow (Monday) we're off to Michigan! It should be ~2,500 miles out and ~2,900 miles back for a round trip of ~5,400 miles total. It's longer on the way back, because we're taking a slight side trip through Texas (and at these distances a 400 mile out of the way drive is only a short detour :- ).

How's my mileage been in my Volt so far? With 15,335 miles total distance my lifetime average is 71 MPG even with all the gas only driving. My average since we finished that first 3,500 miler is a respectable 100 MPG.

That trip odo's getting reset now...

It'll be interesting to see what range we get on the open road. I've been practicing my MM hypermiling on our numerous trips to LA, generally getting about 42-44 MPG. Our last trip to LA showed almost an exact 50/50 split between gas miles and electric miles over the 250 mile trip.

One side effect of that?

All the gas miles in the pulse, and the fuel consumption with it in MM, get averaged into your predicted gas range. So even though I've been getting mid 40s MPG, my car thinks I'm only getting low 20s on gas. So after filling up my tank tonight it thinks I have a gas range of only about 200 miles! That'll make range estimations a challenge 'till we figure it out on the open road...
 

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Hello Rusty, I am curious to know with that many gas miles have you noticed what your oil life sensor % reads. Inquiring minds want to know.
 

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Our last trip to LA showed almost an exact 50/50 split between gas miles and electric miles over the 250 mile trip.
Wow! How did you accomplish that? Multiple stops and charging along the way? (Nissan Leaf mode)

Have a good trip and a safe trip. I have 9,537 miles on Volt #2398 since April, of which 4,406 (46%) have been as an EV. My lifetime MPG is 70.1. And that's with climate control on COMFORT and no hypermiling.

I'm heading on another trip to babysit and chauffeur the grandkids, but we're going to need room for at least 5, so the Volt is staying home this time and we're driving the Yukon XL. We obviously won't get the 45 MPG we would get on a 500 mile round trip in the Volt.
 

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Hello Rusty, I am curious to know with that many gas miles have you noticed what your oil life sensor % reads. Inquiring minds want to know.
My oil life is at 76% after 9,537 miles, of which 4,406 have been EV (5,131 CS miles, engine not running all the time)
 

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Well, after almost 6,500 miles I'm FINALLY going to get to take a road trip this next weekend, albeit a short one, <500 miles, but that still beats just commuting to and from work. I plan on "playing" with MM and hope that my overall average for the trip is at least in the mid 40's.

We'll see.
 

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Wow! How did you accomplish that? Multiple stops and charging along the way? (Nissan Leaf mode)
In case Rusty is off traveling and can't get back to you for a while, he's using MM as a form of "Pulse & Glide" on steroids. He starts in MM, then goes to Normal where he uses the battery, then back to MM. Repeat. The idea is the delta of RPMs needed to charge the battery in MM is sufficiently small relative to the gas saved when using the energy discharged by the battery. Making up numbers, driving in Normal might use one gallon of gas every 35 miles. Using his MM/Normal technique he uses one gallon for 20 miles but then gets to drive on batteries for 20 miles. That means he's using one gallon of gas for 40 miles.

I'm sure he'll give you more detail after this trip!
 

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Discussion Starter · #9 ·
In case Rusty is off traveling and can't get back to you for a while, he's using MM as a form of "Pulse & Glide" on steroids. He starts in MM, then goes to Normal where he uses the battery, then back to MM.
Late morning this morning, we're stopping in Vegas tonight ('cause we expected a late start and didn't want to drive all the way to St. George). First, as to oil life - 62% remaining. Of the 15,335 driven that's 8,163 electric and 7,172 gas or 53% electric overall (as reported by MyVolt).

As for MM hypermiling, that's not quite what I do. I start in Normal Mode, and drive until the SOC is down to 1 (ONE) bar (about 4 miles remaining). Then I switch to Mountain Mode for 15-20 minutes (depending on traffic, which in the trial runs to LA was... variable).

At that point I should then have 4 bars SOC in the battery (SURE WOULD BE NICE IF THE CAR WOULD TELL ME WHEN THAT HAPPENS, OR WOULD AT LEAST INDICATE TRUE SOC!), then I go back to Normal Mode. The car then glides along electrically until I get back to 1 (ONE) bar (about 4 miles remaining).

Switch back to Mountain Mode and repeat ad naseaum.

The thought is that with the engine running at higher RPMs than it normally would, it runs at a more efficient SFC. IIRC the charts we've seen on those details bare that out, and it's certainly so far been my experience. Are the higher engine RPMs annoying? Not for me, at least not at 70+ MPH (I try to avoid MM pulse below 65). The road noise covers it. Is it a much more involved driver experience (aka "PITA")? Yup. But I don't see how the car could have the smarts to do it itself.

And so, we're off. I should have network connectivity on the road once we get checked in at various hotel/motels. But even though we're staying in Vegas tonight (and very well off the strip, I might add)... I'm not a betting man.

Once we get to up-state Michigan, all bets are off. The Victorian cottages of Bayview are often barely wired for the last century, much less this one!
 

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OFF TO VEGAS THEN MICHIGAN!!
That's awesome.
Enjoy your journey my friend
WOT
 

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Bayview OMG, you will love it, My sister runs a B&B on Mackinaw Island and just bought a house there. She is winter crazy.
 

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I start in Normal Mode, and drive until the SOC is down to 1 (ONE) bar (about 4 miles remaining). Then I switch to Mountain Mode for 15-20 minutes [...] The thought is that with the engine running at higher RPMs than it normally would, it runs at a more efficient SFC. IIRC the charts we've seen on those details bare that out, and it's certainly so far been my experience. Are the higher engine RPMs annoying? Not for me, at least not at 70+ MPH (I try to avoid MM pulse below 65). The road noise covers it. Is it a much more involved driver experience (aka "PITA")? Yup. But I don't see how the car could have the smarts to do it itself.
With all due respects, I think you are just cooking the books on EV miles. I can easily get 45 MPG on a 500 mile round trip, plugging in at each end - 40 miles electric and about 40 MPG in normal mode; this with auto climate control on COMFORT 72 and keeping up with the predominant flow of traffic (70 - 75 MPH). You say you got 42-44 with your mountain mode cycling.

I would believe that GM's engineers have optimized the engine for the best EPA fuel economy numbers attainable, particularly with the spotlight on the Volt. If this could have been obtained by higher RPM's ala mountain mode then battery, they would have done this. I've commented before how much the Volt runs on battery alone (engine off) in CD mode (showing the blue gas gauge), particularly when you encounter stop and go traffic, or when the speed drops to 50 MPH in a construction zone. Granted, it shows up as 40 miles electric (green) and 210 miles gas (blue), but the bottom line is gallons of gas used. In my case, 210 miles at 40 MPG is 5.25 gallons used. Add in the 40 miles electric, and 250/5.25 = 47.6 MPG. I'd venture to say it costs 5 times as much to get those miles of electric range by running the gas engine at high RPM than it costs just plugging in.
 

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Discussion Starter · #14 · (Edited)
With all due respects, I think you are just cooking the books on EV miles.
Well, you can accuse me of cooking the books as you wish. But I try to make sure to document by book cooking so that others may try and replicate my results.

We're in the motel in Vegas. I'll write an update on the first day a little later. The short summary is "It's bad to be playing with gaming Mountain Mode, and run in to an actual mountain at a bad time"...
 

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"Cooking books" implies falsifying the numbers. I don't think Rusty is doing that at all.

I don't use Mt. mode. I've gone 10,342 miles, only 5,197 of which were electric, making my electric miles 50% of total miles, which is slightly lower than Rusty's 53%, and my lifetime is 75 MPG. My MPG is 4 higher than Rusty's even though I have a slightly lower percentage of electric miles probably because my avg. gas speed is lower than his.

No book-cooking necessary. The numbers are what they are.
 

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The only "book cooking" I see appears to be the EV miles artificially inflated from the Volt's point of view.

It would be best if people just reported MPG-CS, then we are always comparing the same thing, and %EV doesn't have to be accounted for. Honeiritiscom's mileage would thus be ~37.x MPG-CS. Rusty's MPG-CS would be more difficult to calculate since his car would be reporting what were really gas miles as EV miles. He should subtract only the "wall EV" miles from his total, divide by gas used to get his MPG-CS.

I'm probably going to experiment with the MM gaming after I get my car, but I'll probably let the car get into CS mode before trying the MM/normal alternation so they all get tallied as CS miles. I'll use the energy monitor screen to see when charge runs out.

GM well could have chosen somewhat lower efficiency in favor of a quieter, more seamless EV->gas transition. More data gathering from different owners seems to be in order.
 

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With all due respects, I think you are just cooking the books on EV miles.
Maybe an unfortunate turn of phrase. I think you're saying that you get roughly the same mileage as he is reporting without using MM. Hence what you're saying is that he's underestimating the MPG he'd get driving the car without gaming MM, not that he's making up numbers when gaming MM. I don't BTW think he's reporting the numbers in the way you're suggesting but we'll know soon enough.

I don't think the GM engineers would have set the car up with way. It's a rather distracting driving experience. Personally I wouldn't like having the engine come on all the time at high RPMs. I'd rather have a quieter less efficient drive. But keep in mind that I would definitely not go through the machinations he is in order to boost MPG unless there was a big number at the end of the day.

I am though interested in how it's working. Very cool.
 

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Discussion Starter · #18 ·
OK, first the numbers:

Yesterday, 8/8, we pulled into Vegas driving 357.7 miles, consuming 8.9 gallons, for 40.1 MPG.
Today, 8/9, we pulled into Clifton CO driving 512.7 miles, consuming 13.4 gallons, for 38.0 MPG.
Trip total so far is 870.5 miles, 22.4 gallons, for 38.8 MPG.

Now, as to yesterday's drive... I was doing fine doing the P&G. I made sure to have a good head of steam before hitting the pass between Riverside and Victorville, so no problems there. But I forgot about the "hill" outside of Baker. Hit the bottom of it with only 3 miles indicated EV range, hitting MM as I realized my mistake. Too late. The hill was too much for the car, and about half way up the engine declucthed and revved high. I slowed from 74 to 69 (to give the main motor a chance) but by 2/3rds the hill I got the "reduced power" message. And it meant it as I slowed gradually down to 60. Fortunately there's a truck a lane...

But I went from 42 MPG at the base of the hill to 37 by the top. Reduced power mode sucks gas like a pig!

My wife had said the hotel that night had nowhere to plug in, so we pulled into town with 8 miles EV available (from MM). Turns out they kinda did have power, only the breaker tripped after the car had loaded 28 miles (I think when the sun came up and things started to heat up again). Heading out of town, and deciding Vegas really is in a valley, I switched to MM with 7 miles EV showing. And the hills and climbs started. The Virgin River climb is impressive, but the car had no trouble (even at 70-75).

Then things got strange. Heading into St. George I didn't expect MM to add much. But I could NOT get very many MM added miles after that, throughout all of southern Utah. Even after an hour of MM driving along a gradual slope (with ups and downs) my EV range went from 6 miles to 9.

I know GM tested the heck out of MM on Pikes Peak (at 70 MPH). But did they test in southern Utah at 6-7.5K feet at 75-80 MPH? Fortunately I was able to make it without any trouble if I'd had a one hour layup into a real mountain, I don't see how the Volt could have made it at speed. But in the future if I know I'm driving really hilly terrain (like tomorrow's drive through Denver) I'll start in MM and just keep it there.

So no more P&G until the plains!
 

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It seems like the car should have just about enough smarts to kick on MM by itself. The nav maps would need elevation data to be able to add that feature.
 

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Discussion Starter · #20 ·
OK, I can't explain today's results. I just can't.

Today's travel was from Clifton CO (a suburb of Grand Junction, which is a really nice town and area) to Paxton NE (which has a so-so hotel (yes, just the one), but a really kick *ss steak house (if you don't mind taxidermy)). But the numbers are what they are. We left Clifton with a full charge, and as I said yesterday I switched straight away to MM. Heading up the climb we got about 20 miles before the generator kicked on. OK, I can understand that part. But here's the numbers:

8/10
Miles traveled: 466.5
Gallons used: 10.5
MPG 44.1

WHAT!!?! 44.1, with some of the most serious mountain climbing in the country and after that a long run of nearly 80 MPH? Worse yet, as we pulled through Denver at about 240 miles traveled, I had 48.5 MPG! What's worse, most of the way up the mountain I sped as best I could ("Hey, the speed limit says 60 - but that's for semis... I can still do 75, right?" and "I know it says 75, but that really means not quite 80, right?). And this was all in Mountain Mode until I started down the big grade. Granted, there was one spot of a few miles of 15-40 MPH travel for construction, but still...

So I have no idea why the excellent gas mileage today. Here's the trip total so far:

Miles Driven: 1337.0
Gallons used: 32.9
MPG: 40.5

That 40.5 MPG overall does include 2 full charges, and 1 charge to 80%. If a charge is a gallon that's still 37.5 MPG overall.

But I also have a *major* concern.

As I said yesterday, Mountain Mode doesn't seem to be able to bring the car back up to charge as you continue up a long climb. Today, when I hit that construction just a few miles before the tunnel the ICE continued to hum away at quite a nice pace, refilling the battery. Right? So I clicked it over to Normal Mode to see how many miles I had in EV after this *long* climb up the mountain. I had 3, so I clicked it right away back to MM. After some 4-5 miles and 20 minutes of low speed driving with moderately high revving engine, when we hit clear driving again I clicked it back to NM to see how much EV ranged I'd gained.

It read 4. I'd gained 1 silly mile. And it was a problem.

As I headed up the final slope towards the tunnel the engine sped higher and higher, until *just* before I got to the tunnel it revved to the max RPM it does just before it starts into its reduced power mode.

I'm nearly certain that had I been able to drive up from Grand Junction towards Denver without hindrance, even though I'd been in Mountain Mode the entire way, I would have dropped to reduced power mode and had to crawl up the last bit of climb.

It appears to me Mountain Mode was engineered and tested by GM to be just that. Mountain. Pick one. Drive along a nice flat terrain in Mountain Mode for 20 miles or so, climb that one mountain, then go down the other side. Mountain Mode's done, it climbed it's one mountain.

What Mountain Mode *doesn't* appear to be is "Mountainous Mode". It didn't handle Southern Utah well yesterday. It didn't handle the long climb up from Grand Junction today. It just doesn't seem to handle continuous waves of peaks and valleys.

It's "Pick One Mountain and Drive That One" Mode.

I've heard GM picked this same particular mountain to test MM. But if I recall, it was "Drive up from Denver, say 'good, it worked!', then drive back down."

That's not how mountainous driving works in the west, and it would be really easy for even a casually good driver to run out of "go juice" even with somewhat modest driving in mountainous terrain.

Mountain Mode seems to just give up after one.
 
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